Traditionally, European consumers are familiar with in-wash dosing devices to administer both liquid and granular detergents when using an automatic washing machine. These in-wash dosing devices are typically filled with laundry detergent and placed directly in the drum during the washing process. This is due to the unique structure of European washing machines which fill the drum after the sump pump, below the drum, is filled. Thus, the dosing device is used to measure the detergent and also to prevent the detergent from filtering through the drum and into the sump pump prior to the drum filling.
In contrast, North American and Japanese consumers typically only use in-wash dosing devices but instead use a simple measuring device to properly measure the recommended amount of detergent for their washing cycle. This is because most North American and Japanese washing machines do not use a sump pump system but instead fill the washing drum immediately. As a result, the laundry detergent placed within the drum remains there regardless of when the detergent is added. For this reason, North American and Japanese consumers are unfamiliar with in-wash dosing devices which are placed within the washing drum.
The evolution of a highly viscous liquid laundry detergent product creates a need for a unique global dosing device. This highly viscous liquid laundry detergent has at least 40% suspended solids and sticks to all surfaces due to it containing both hydrophobic and hydrophilic species. As a result, this highly viscous detergent cannot be simply measured in a measuring device and poured into the washing drum as it will stick to the device. Therefore, like the European washing process, this highly viscous detergent must be measured in an in-wash dosing device and placed within the washing drum to ensure that the detergent is washed from the device during the washing process.
Unfortunately, washing machines used world-wide do not function in a similar manner. For example, U.S. and Japanese washing machines typically include a short cycle, cold wash, and low agitation. In contrast, European washers typically have a long cycle, warm wash, and high agitation. As a result, conventional in-wash dosing devices do not function properly to adequately dispense highly viscous liquid laundry detergent. These in-wash dosing devices are typically solid and float on top of the water in top loading washing machines. This can result in the liquid detergent remaining within the dosing device during the wash cycle which prevents the detergent from functioning properly. To solve this, the consumer could be required to add water to the in-wash dosing device to ensure that the device sinks, but this is not reliable nor feasible.
Therefore, what is needed is an in-wash dosing device for a highly viscous liquid laundry detergent which provides an accurate and complete transfer of the viscous detergent from the dosing device to the wash water within the washing machine.